code: def subtest_order_counts(self):
      if self.k < 2:
          return
  
      ordered_pairs = [(i, j) for j in range(self.k) for i in range(j)]
      cnt = np.zeros(len(ordered_pairs))
  
      for s in self.samples:
          for t, (i, j) in enumerate(ordered_pairs):
              if s[i] < s[j]:
                  cnt[t] += 1
  
      m = len(self.samples)
  
      mean = m / 2
      std = np.sqrt(m / 4)
  
      self.subtest_normal_distrib(cnt, mean, std)
  
file_path: pfrl/tests/utils_tests/test_random.py
imports: import timeit
  import unittest
  import numpy
  import pytest
  from scipy import stats
  from pfrl.utils.random import sample_n_k
label_desc: Use image node_id 6 for calling the TestSampleNK obj's underlying member method code with example usage: obj.subtest_order_counts() without return types